Table 2
Agreement between arterial and venous pCO2, pH and HCO3−
| ABG (mean) (SD) | VBG (mean) (SD) | Mean difference (ABG–VBG) (95% CI) | 95% limits of agreement | N | |
|---|---|---|---|---|---|
| pH | 7.40 (0.09) | 7.37 (0.08) | 0.03 (0.02 to 0.04) | −0.05 to 0.11 | 234 |
 (mEq/L) | 29.7 (6.3) | 29.7 (6.4) | −0.04 (−0.22 to 0.15) | −2.90 to 2.82 | 232 |
| pCO2 (kPa) | 6.89 (2.40) | 7.63 (2.41) | −0.75 (CI −0.89 to −0.61) | −2.91 to 1.41 | 225 |
ABG, arterial blood gas; VBG, venous blood gas.